The invention relates to an insulation material for use on a heat-conducting pipe as well as an insulation element for a pipe in the vicinity of a wall or ceiling duct.
From prior art, it is known to protect pipes passing through a wall or a ceiling in a fire protection-related manner to prevent the fire from spreading. To ensure fire protection, mineral wool fiber shells of approx. 1 m in length are typically used as insulation material and are laid around the pipe to be protected. The insulation material used thereby extends to the wall and is applied to both sides of the wall. To prevent a burn-through, an annular gap in the wall, which is formed when the pipe is run through a wall opening, is also sealed with a sealing agent. The thickness of the insulation material used is thereby dependent on the maximum permissible temperature in the vicinity of the wall and the expected temperatures.
Among the known insulation materials, it has proven to be disadvantageous that their insulating effect is so good that for very heat-conductive pipes, such as aluminum pipes, an elevated temperature occurs on the side of the insulation facing away from the wall and that lies outside the desired temperature range. The temperature rose partly above the critical range, i.e., a temperature increase of more than 180° K. was observed. The possibility of the fire spreading via the heated pipe hereby exists.
It is thus the object of the invention to provide an insulation material, which ensures that the temperature of the insulation always lies in the desired range.
According to the invention, the object is achieved by means of an insulation material for use on a heat-conducting pipe, with an exterior surface and an interior surface, which, when used, lies against the pipe to be insulated, wherein the exterior surface, when used on the pipe to be insulated, defines the exterior circumference of the insulation material, which varies over the axial length of the insulation material (corresponds to the axial expansion of the pipe). In this way, the insulating effect of the insulation material can vary over the axial length, so that for example good insulation is possible in one region, and a higher heat dissipation is possible in another section. Generally, one can thereby improve the fine adjustment of the insulation element.
According to one aspect of the invention, it is provided that the exterior circumference diminishes toward a free end of the insulation material, i.e., the thickness of the insulation material decreases starting at the wall or ceiling in an axial direction of the pipe. A high degree of insulation in the vicinity of the wall and higher heat dissipation toward the free end of the insulation material is thereby achieved, so that the high temperatures in the wall region are not conveyed to the free end. All in all, the heat dissipation can thus to a large extent be kept constant over the axial length of the insulation material.
In particular, the exterior circumference is largest in the vicinity of a wall through which the insulating pipe passes. This offers the advantage that the insulation is greatest in the vicinity of the wall, since this is where the expected temperatures are also the highest.
According to another aspect of the invention, it is provided that the insulation material has a section that extends with the pipe to be insulated through a wall opening. This means that the insulation material can be pushed through a wall opening, whereby the insulation material is also present inside the wall. As a result, the pipe to be insulated is insulated on both sides of the wall through which the pipe passes.
Furthermore, one can omit a sealing agent in the annular gap if the section is correspondingly fitted to the wall opening.
In particular, the exterior surface runs in an essentially conical or frusto-conical manner. This represents an optimal geometry of the insulation material, whereby a very good compromise between insulation and heat dissipation is possible, so that an even temperature trend is achieved over the entire axial length of the insulation material.
Another aspect of the invention provides that the interior surface is structured, having in particular nubs or conical and/or wedge-shaped ribs. The structuring enables one to achieve that the insulation material, when wrapping the pipe, is ideally adjusted, particularly to varying pipe radii. In addition, the structuring enables one to adjust the insulation and heat dissipation behavior.
Furthermore, it is provided that the exterior surface, in its cross-section, runs in a roughly hyperbola-shaped manner. In terms of its heat conductivity and insulation property, the insulation material can be adjusted optimally to the temperature trend, so that the temperature is constant over the axial length.
Another aspect of the invention provides that the insulation material consists of a very elastic insulation material, particularly an insulation foam or mineral wool. These materials are particularly well suited since they are very malleable and thus can be simply placed around the pipe to be insulated.
Suitable materials that exhibit no intumescence in the event of fire are for example polyethylene (PE), polyurethane (PUR), rubber, or ethylene-propylene diene monomers (EPDM).
Alternatively, particularly when larger annular gaps up to approximately 10 nm are to be sealed, intumescent foam materials can also be used. These consist of a foamable binding agent that contains an intumescent substance mixture. The binding agent thereby serves as a bond-forming carrier for the intumescent substance mixture. Preferably, the substance mixture is distributed homogeneously in the binding agent. The bond-forming carrier is preferably selected from the group consisting of polyurethanes, phenol resins, polystyrenes, polyolefins, such as polyethylene and/or polybutylene, melamine resins, melamine resin foams, synthetic or natural rubber, cellulose, elastomers and blends thereof, wherein polyurethane is preferred.
The ash-forming and if applicable intumescent substance mixture includes the conventional fire protection additives known to a person skilled in the art, which in the event of fire, in other words when exposed to heat, foam up and thereby form a flame propagation-impeding foam, such as an intumescent material on the basis of an acid-forming substance, a carbon-supplying compound, and a gas-forming substance. Preferably, the intumescent material includes: as acid-forming substances, a salt or an ester of an inorganic, non-volatile acid selected from sulfuric acid, phosphoric acid, and boric acid; as a carbon-supplying compound, a polyhydroxy compound and/or a thermoplastic or thermosetting polymeric resin binding agent; and as a gas-forming substance, a chlorinated paraffin, melamine, a melamine compound particularly melamine cyanurate, melamine phosphate, melamine polyphosphate, tris(hydroxyethyl)-cyanurate, cyanamide, dicyanamide, dicyandiamide, biguanidine, and/or a guanidine salt, particularly guanidine phosphate or guanidine sulfate.
The compound-forming carrier can also contain as an ablative additive an inorganic compound, which has water, e.g., as crystal water, firmly embedded in it and does not dry out at temperatures up to 100° C., but does release it starting at 120° C. in the event of fire. Temperature-conducting parts can thereby be cooled. Preferred is an inorganic hydroxide or hydrate releasing water at the fire temperature or when exposed to flame, particularly aluminum hydroxide, aluminum oxide hydrates or partially hydrated aluminum hydroxides. However, one can consider other inorganic hydroxides or hydrates releasing water when exposed to flame, as they are described in EP 0 274 068 A2.
Such compounds that can be used as substance mixtures in the fire protection insert according to the invention are known to a person skilled in the art and are disclosed for example in the following publications, which are hereby explicitly referred to: DE 30 25 309 A1, DE 30 41 731 A1, DE 33 02 416 A1, DE 34 11 327 A1, EP 0 043 952 B1, EP 0 051 106 B1, EP 0 061 024 B1, EP 0 116 846 B1, EP 0 158 165 B1, EP 0 274 068 A2, EP 1 347 549 A1, EP 1 641 895 B1 and DE 196 53 503 A1.
The fire protection insert can be produced for example by mold foaming, such as reaction foaming (RIM) according to DE 3917518, e.g., with Fomox® fire protection foam or the barrier layer-forming construction material HILTI CP 65GN. Materials that can be used for purposes according to the invention are known from EP 0061024 A1, EP 0051106 A1, EP 0043952 A1, EP 0158165 A1, EP 0116846 A1 and U.S. Pat. No. 3,396,129 A as well as EP 1347549 A1. The molded object preferably consists of an intumescence-capable polyurethane foam as it is known from EP 0061024 A1, DE 3025309 A1, DE 3041731 A1, DE 3302416 A and DE 3411 327 A1.
Another aspect of the invention provides that a fabric insert is provided, particularly in the region of the interior surface. The fabric insert thereby serves to improve the wrappability of the insulation material.
The insulation material can be designed to consist of one piece or of multiple layers. In the one-piece design of the insulation material, it consists of a wedge-shaped mat for example, which is wrapped around the pipe to be insulated. Alternatively, it is also possible that the insulation material consists of multiple layers, wherein the number of layers increases toward the wall through which the pipe extends. In this way, an approximately wedge-shaped cross-section of the insulation is obtained, which runs in a step-like manner due to the layers.
Another aspect of the invention is that the insulation material has on the exterior surface an additional adhesive tape, particularly an adhesive tape with glass fiber filaments. This adhesive tape ensures that the applied insulation material is fixed to the pipe. The glass fiber filaments melt at elevated temperatures, and a ceramic-like material-melt-decomposition product, which ensures secure fixation of the insulation material to the pipe to be insulated, is formed.
Furthermore, the invention relates to an insulation element for a pipe in the vicinity of a wall or ceiling duct, with an insulation material that surrounds the pipe, wherein the insulation material extends to the wall or ceiling, or extends through the duct itself, wherein the insulation element has a larger diameter at the axial end facing the duct than on the axial end facing away from the duct. For such an insulation element, an insulation material of the aforementioned type can be used, wherein the aforementioned advantages apply analogously for the insulation element.
The insulation material according to the invention and the insulation element according to the invention are used for insulating pipes, particularly heat-conducting pipes, wherein the pipes themselves may already be furnished with an insulation element not equipped to protect against fire.
The insulation may be produced as a pipe shell or as roll material, wherein the roll material is preferred.
Additional advantages and features of the invention are found in the description below and in the drawings below that are referred to.